London has a severe air quality problem. The issue reached a critical point in January when the EU-approved annual limit for pollution was breached after just three days into the year.

The Mayor of London decided to take action to tackle the city’s terrible congestion and lethal air pollution.

The £10 Toxicity Charge (T-Charge), launched today, is designed to get older more polluting cars off the road.

Whether you live in London or just passing through, here’s what you need to know about the new legislation:

Drivers of the more polluting petrol and dirty diesel vehicles will pay the new T-Charge plus the Congestion Charge (C-Charge) – a total of £21.50 (£10 T-Charge and £11.50 C-Charge) every weekday they drive in the zone from 7am-6pm.

The T-Charge will affect up to 34,000 polluting vehicles every month – those that do not meet the Euro 4 standards for both PM and NOx emissions.

Pre-Euro 4 vehicles are typically those registered before 2006 that are approximately over 12 years old, but TfL advise anyone who has a car registered before 2008 to check if their vehicle is eligible for the charge.

To find out if your vehicle is affected, look at Transport for London’s free online vehicle checker www.tfl.gov.uk/t-charge.

The T-Charge is designed to prepare drivers for the early introduction of the Ultra-Low Emission Zone, which Sadiq Khan is proposing to introduce as early as April 2019 and which will affect thousands more vehicles in the existing congestion zone, including all diesel vehicles that do not meet Euro 6 standards.

Recent health data has shown 7.9 million Londoners – nearly 95 per cent of the population – live in areas exceeding the World Health Organisation guidelines on toxic air quality particles. It is estimated that air pollution contributes to thousands of premature deaths each year in London, as well as having effects over the course of our lives.

Since Sadiq announced the T-Charge in February, the daily number of older more polluting vehicles driving into the Congestion Zone has decreased by about 15 per cent.

TfL expect that the T-Charge will result in a further drop, with around 40 per cent of motorists upgrading their vehicles and around 10 per cent switching to alternatives like public transport in the first year.

TfL will use a camera-based mechanism for enforcement of the T-Charge, monitoring both diesel and petrol vehicles.

The T-Charge is one of the measures the Mayor is introducing to improve London’s toxic air quality. Others include doubling funding spent on tackling air quality and consulting on an earlier introduction of the central London ULEZ in 2019. He is also developing proposals for a London-wide Euro VI standard for heavy vehicles in 2020 and expanding the ULEZ up to the North/South Circular roads for cars, vans and motorcycles in 2021.

The Mayor wants to encourage people to make fewer journeys in polluting vehicles, and consider greener methods of transport including using public transport, walking or cycling.

Prof. Stephen Holgate, from the Royal College of Physicians said: “The implementation of the T-charge is a positive step towards cleaning up London’s air and it is showing to the world that it is possible to change behaviours in order to reduce the harms from high polluting vehicles. Such actions will improve the air quality in our capital and in time will save lives.”

Rosie Rogers, clean air campaigner at Greenpeace, added: “London now joins Paris, Copenhagen and many other progressive cities in taking urgent steps towards removing polluting diesel cars from their streets. The ball is now in the court of our national government to grasp the urgency of the crisis and take more meaningful action to reduce the illegal levels of air pollution seriously harming people’s health across the UK.”